Electric motor control unit

摘要

An electric motor control unit mounted in an automotive vehicle has a motor (3) that is variable in its rotational speed. A temperature sensing element (18s) is arranged to contact a busbar so that relays (15b) and (15c) permit switching operation in response to detection of abnormal heat generation. This controls an electrical power supply to the motor to decrease the rotational speed of the motor without complete stopping of the motor. The rotational speed of the motor returns to a normal speed from the decreased speed by switching operation of the relays (15b) and (15c) with diminishing of the abnormal heat generation.